U.S. patent application number 16/307685 was filed with the patent office on 2019-10-03 for method for providing contention-free random access resources for nb-iot.
The applicant listed for this patent is TELEFONAKTIEBOLAGET LM ERICSSON (PUBL). Invention is credited to Bela Rathonyi, Magnus Stattin.
Application Number | 20190306887 16/307685 |
Document ID | / |
Family ID | 59101534 |
Filed Date | 2019-10-03 |
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United States Patent
Application |
20190306887 |
Kind Code |
A1 |
Rathonyi; Bela ; et
al. |
October 3, 2019 |
METHOD FOR PROVIDING CONTENTION-FREE RANDOM ACCESS RESOURCES FOR
NB-IOT
Abstract
A method (800) in a network node (115) comprises reserving
(804), within a Narrowband Physical Random Access Channel (NPRACH)
resource (305, 405, 505, 605, 705) comprising a plurality of start
subcarriers, a subset of the plurality of start subcarriers for
performing a contention-free random access procedure (310, 410,
520, 530, 610, 720, 730). The method comprises communicating (804),
to one or more user equipment (UEs) (110), information indicating
which of the plurality of start subcarriers within the NPRACH
resource are reserved for performing the contention-free random
access procedure.
Inventors: |
Rathonyi; Bela; (LOMMA,
SE) ; Stattin; Magnus; (UPPLANDS VASBY, SE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TELEFONAKTIEBOLAGET LM ERICSSON (PUBL) |
Stockholm |
|
SE |
|
|
Family ID: |
59101534 |
Appl. No.: |
16/307685 |
Filed: |
June 8, 2017 |
PCT Filed: |
June 8, 2017 |
PCT NO: |
PCT/IB2017/053406 |
371 Date: |
December 6, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62347584 |
Jun 8, 2016 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W 74/0833 20130101;
H04L 67/12 20130101; H04L 5/0012 20130101; H04W 72/0453 20130101;
H04L 5/0053 20130101; H04L 5/0094 20130101 |
International
Class: |
H04W 74/08 20060101
H04W074/08; H04W 72/04 20060101 H04W072/04 |
Claims
1. A method in a network node (115), the method comprising:
reserving within a Narrowband Physical Random Access Channel
(NPRACH) resource comprising a plurality of start subcarriers, a
subset of the plurality of start subcarriers for performing a
contention-free random access procedure; and communicating (804),
to one or more user equipment (UEs), information indicating which
of the plurality of start subcarriers within the NPRACH resource
are reserved for performing the contention-free random access
procedure.
2. The method of claim 1, wherein: the information indicating which
of the plurality of start subcarriers within the NPRACH resource
are reserved for performing the contention-free random access
procedure comprises a number of start subcarriers within the NPRACH
resource that are not reserved for performing the contention-free
random access procedure.
3. The method of claim 2, wherein the start subcarriers within the
NPRACH resource that are not reserved for performing the
contention-free random access procedure are available for
performing a contention-based random access procedure.
4. The method of claim 2, wherein the information is signaled as
part of a radio resource control information element.
5. The method of claim 1, wherein: each of the plurality of start
subcarriers within the NPRACH resource is a first subcarrier for a
subcarrier hopping sequence.
6. The method of claim 1, comprising: communicating, to a first UE,
an instruction to use a particular one of the reserved start
subcarriers for performing the contention-free random access
procedure.
7. The method of claim 1, wherein: the information indicating which
of the plurality of start subcarriers within the NPRACH resource
are reserved for performing the contention-free random access
procedure comprises a number of reserved start subcarriers.
8. A method in a user equipment (UE), comprising: receiving, from a
network node, information indicating which of a plurality of start
subcarriers within a Narrowband Physical Random Access Channel
(NPRACH) resource are reserved for performing a contention-free
random access procedure; and performing a random access procedure
based on the received information.
9. The method of claim 8, wherein: the start subcarriers that are
reserved for performing the contention-free random access procedure
comprise a subset of the plurality of start subcarriers within the
NPRACH resource; and one or more start subcarriers that are not in
the reserved subset are available for performing a contention-based
random access procedure.
10. The method of claim 9, wherein: the information indicating
which of the plurality of start subcarriers within the NPRACH
resource are reserved for performing the contention-free random
access procedure comprises a number of the one or more start
subcarriers that are not in the reserved subset.
11. The method of claim 10, comprising: determining which of the
plurality of start subcarriers are reserved for performing the
contention-free random access procedure based on the number of the
one or more start subcarriers that are not in the reserved
subset.
12. The method of claim 10, comprising: selecting a first start
subcarrier from among the one or more start subcarriers that are
not in the reserved subset; and wherein performing the random
access procedure based on the received information comprises
performing a contention-based random access procedure using the
selected first start subcarrier.
13. The method of claim 9, comprising: receiving, from the network
node, an instruction to use a particular one of the reserved start
subcarriers for performing a contention-free random access
procedure; and wherein performing the random access procedure based
on the received information comprises performing the
contention-free random access procedure using the particular one of
the reserved start subcarriers.
14. The method of claim 8, wherein: the information indicating
which of the plurality of start subcarriers within the NPRACH
resource are reserved for performing the contention-free random
access procedure comprises a number of reserved start
subcarriers.
15. The method of claim 8, wherein the information is received in a
radio resource control information element.
16. The method of claim 8, wherein: each of the plurality of start
subcarriers within the NPRACH resource is a first subcarrier for a
subcarrier hopping sequence.
17. A network node, comprising: processing circuitry, the
processing circuitry configured to: reserve, within a Narrowband
Physical Random Access Channel (NPRACH) resource comprising a
plurality of start subcarriers, a subset of the plurality of start
subcarriers for performing a contention-free random access
procedure; and communicate, to one or more user equipment (UEs),
information indicating which of the plurality of start subcarriers
within the NPRACH resource are reserved for performing the
contention-free random access procedure.
18. The network node of claim 17, wherein: the information
indicating which of the plurality of start subcarriers within the
NPRACH resource are reserved for performing the contention-free
random access procedure comprises a number of start subcarriers
within the NPRACH resource that are not reserved for performing the
contention-free random access procedure.
19. The network node of claim 18, wherein the start subcarriers
within the NPRACH resource that are not reserved for performing the
contention-free random access procedure are available for
performing a contention-based random access procedure.
20. The network node of claim 18, wherein the information is
signaled as part of a radio resource control information
element.
21. The network node of claim 17, wherein: each of the plurality of
start subcarriers within the NPRACH resource is a first subcarrier
for a subcarrier hopping sequence.
22. The network node of claim 17, where the processing circuitry is
configured to communicate, to a first UE, an instruction to use a
particular one of the reserved start subcarriers for performing the
contention-free random access procedure.
23. The network node of claim 17, wherein: the information
indicating which of the plurality of start subcarriers within the
NPRACH resource are reserved for performing the contention-free
random access procedure comprises a number of reserved start
subcarriers.
24. A user equipment (UE) comprising: processing circuitry, the
processing circuitry configured to: receive (904), from a network
node, information indicating which of a plurality of start
subcarriers within a Narrowband Physical Random Access Channel
(NPRACH) resource are reserved for performing a contention-free
random access procedure; and perform a random access procedure
based on the received information.
25. The UE of claim 24, wherein: the start subcarriers that are
reserved for performing the contention-free random access procedure
comprise a subset of the plurality of start subcarriers within the
NPRACH resource; and one or more start subcarriers that are not in
the reserved subset are available for performing a contention-based
random access procedure.
26. The UE of claim 25, wherein: the information indicating which
of the plurality of start subcarriers within the NPRACH resource
are reserved for performing the contention-free random access
procedure comprises a number of the one or more start subcarriers
that are not in the reserved subset.
27. The UE of claim 26, wherein the processing circuitry is
configured to: determine which of the plurality of start
subcarriers are reserved for performing the contention-free random
access procedure based on the number of the one or more start
subcarriers that are not in the reserved subset.
28. The UE of claim 26, wherein: the processing circuitry is
configured to select a first start subcarrier from among the one or
more start subcarriers that are not in the reserved subset; and the
processing circuitry configured to perform the random access
procedure based on the received information comprises processing
circuitry configured to perform a contention-based random access
procedure using the selected first start subcarrier.
29. The UE of claim 25, wherein: the processing circuitry is
configured to receive, from the network node, an instruction to use
a particular one of the reserved start subcarriers for performing a
contention-free random access procedure; and the processing
circuitry configured to perform the random access procedure based
on the received information comprises processing circuitry
configured to perform the contention-free random access procedure
using the particular one of the reserved start subcarriers.
30. The UE of claim 24, wherein: the information indicating which
of the plurality of start subcarriers within the NPRACH resource
are reserved for performing the contention-free random access
procedure comprises a number of reserved start subcarriers.
31. The UE of claim 24, wherein the information is received in a
radio resource control information element.
32. The UE of claim 24, wherein: each of the plurality of start
subcarriers within the NPRACH resource is a first subcarrier for a
subcarrier hopping sequence.
Description
TECHNICAL FIELD
[0001] The present disclosure relates, in general, to wireless
communications and, more particularly, to providing contention-free
random access resources for NB-IOT.
BACKGROUND
[0002] In modern cellular radio systems, the radio network has a
strict control on the behavior of the user equipment (UE) (which
may be interchangeably referred to herein as a wireless device or a
terminal). Uplink (UL) transmission parameters like frequency,
timing, and power are regulated via downlink (DL) control signaling
from the base station to the terminal. For instance, by
time-aligning the UL transmissions, orthogonality between UEs can
be achieved in the time domain. This is necessary since the radio
resources are scarce.
[0003] At power-on or after a long standby time, the UE is not
synchronized in the UL. The UE can derive an UL frequency and power
estimate from the DL signals (e.g., DL control signals). However, a
timing estimate is difficult to make because the round-trip
propagation delay between the network node (e.g., a base station
such as an eNodeB (eNB)) and the UE is unknown. So even if the UE
UL timing is synchronized to the DL, it may arrive too late at the
network node receiver because of the propagation delays. Therefore,
before commencing traffic, the UE has to carry out a random access
procedure to the network. After the random access procedure, the
network node can estimate the timing misalignment of the UE UL and
send a correction message.
[0004] FIG. 1 is a signal flow diagram of an example random access
procedure 10. More particularly, FIG. 1 illustrates an example
random access procedure between a UE 110 and a network node 115
(e.g., an eNB). At step 10-1, UE 110 sends a random access preamble
to network node 115. This is illustrated in the example of FIG. 1
as a Msg1: RA Preamble. Usually, a Physical Random Access Channel
(PRACH) is provided for the UE to request access to the network. A
random access preamble is used that is based on a specific sequence
with good auto-correlation. Typically, a UE performing random
access randomly picks a preamble out of a pool and transmits it.
The preamble represents a random UE ID that can be used by the
network node when granting the UE access to the network. To
distinguish between different UEs performing random access,
typically many different preambles exist.
[0005] At step 10-2, network node 115 sends a random access
Response message to UE 110. The network node receiver listens at
all random access opportunities to detect preambles. In case a
preamble is successfully detected, a random access Response that
includes the number of the detected preamble is sent in a special
message on the DL. This is illustrated in the example of FIG. 1 as
a Msg2: RA Response. The random access Response may include, for
example, information related to a Timing Advance, an UL grant, as
well as any other suitable information. A UE that has recently
performed a random access attempt will listen within a certain time
window after the preamble has been sent to receive a random access
Response. If the UE successfully receives the random access
Response, the UE continues with Steps 10-3 and 10-4 of the random
access procedure as shown in FIG. 1 and described in more detail
below. If no random access Response is received within the
specified window, a new attempt is made.
[0006] The time windows for receiving an random access Response
pertaining to different occasions of PRACH (which is periodic) may
overlap. To enable identification of which random access response
pertains to which occasion of PRACH, each PRACH occasion/period is
associated with a Random Access Radio Network Temporary Identifier
(RA-RNTI). The random access Response transmission is addressed to
the RA-RNTI associated with the corresponding PRACH occasion.
[0007] In the example of FIG. 1, UE 110 successfully receives the
random access Response message. At step 10-3, UE 110 sends a random
access Message 3 to network node 115. This is illustrated in the
example of FIG. 1 as a Msg3: RA Message 3. The random access
Message 3 may include, for example, information related to a UE
Identity, a Buffer Status Report (BSR), as well as any other
suitable information.
[0008] At step 10-4, network node 115 sends a random access
Contention Resolution message to UE 110. This is illustrated in the
example of FIG. 1 as Msg4: RA Contention Resolution. The random
access Contention Resolution may include, for example, information
related to an UL grant and/or DL assignment. Because multiple UEs
can request access at the same time, collisions may occur between
requesting UEs. A contention resolution scheme is therefore
implemented to separate the UE transmissions. As described above,
typically many different preambles exist to distinguish between
different UEs performing random access. The network node receiver
can resolve random access attempts performed with different
preambles and send a response message to each UE using the
corresponding random UE IDs. If the contention resolution procedure
is successful, at step 10-5 UE 110 and network node 115 may perform
further UL/DL transmissions.
[0009] In cases where multiple UEs simultaneously use the same
preamble, a collision occurs. In such a scenario, the random access
attempts are likely not successful. This is because the network
node cannot distinguish between the two users with the same random
UE ID. To minimize the probability of collision, the set of
available sequences should be large.
[0010] In Narrowband Internet-of-Things (NB-IoT), the random access
procedure includes transmitting a random access preamble sequence
on subcarriers on a Narrowband Physical Random Access Channel
(NPRACH). One to three NPRACH resources can be configured in a
cell. An NPRACH resource contains a set of 12, 24, 36 or 48
subcarriers defining 1, 2, 3 or 4 sets of 12 subcarriers,
respectively. Each set may optionally be split into 2 partitions
for single/multi-tone Msg3 transmission. In addition, each NPRACH
resource is associated with a repetition level (i.e., the number of
repetitions of the Msg1/preamble transmission). The Medium Access
Control (MAC) layer in the UE selects the start subcarrier as part
of the random access procedure. In some cases, the start subcarrier
is selected randomly from the set of configured subcarriers. In
other cases, the UE selects and uses a signaled subcarrier received
in a Physical Downlink Control Channel (PDCCH) order.
[0011] After this selection, the MAC layer informs the physical
layer that starts the Msg1 transmission on the selected subcarrier
and then applies frequency hopping between subcarriers from the
configured set if the repetition level is larger than one
(according to the frequency hopping rules specified in section
10.1.6 of R1-165963 ("Introduction of NB-IoT in 36.211," CR0224
rev7, Ericsson, 2016 Jun. 3). The frequency hopping is performed
over 12 subcarriers within a 12-subcarrier subset of the NPRACH. In
some cases, the transmission can be characterized by the starting
subcarrier of the hopping sequence. The start subcarrier may also
be referred to as the start subcarrier index or subcarrier index of
the preamble transmission. An NPRACH can be configured with 12, 24,
36 or 48 subcarriers providing 12, 24, 36 or 48 different
preambles, subcarriers, and/or preamble subcarrier hopping
sequences (which may collectively be referred to herein as
"preambles/subcarriers/preamble subcarrier hopping sequences")
characterized by their start subcarrier indices. When performing
random access, a UE chooses randomly one of the configured
preambles/subcarriers/preamble subcarrier hopping sequences.
[0012] For NB-IoT UEs, the RA-RNTI associated with the NPRACH
occasion in which the random access preamble/subcarrier/preamble
subcarrier hopping sequence is transmitted, is computed as:
RA-RNTI=1+SFN_id/4,
where SFN_id is the index of the first radio frame of the specified
NPRACH.
[0013] NPRACH is configured with the NPRACH-ConfigSIB-NB
Information Element (IE) in the Radio Resource Control (RRC)
protocol as described in R2-164573 ("Introduction of NB-IoT in
36.331," CR2231 rev6, Huawei, 2016 Jun. 7) (hereinafter
"R2-164573"). The IE NPRACH-ConfigSIB-NB is used to specify the
NPRACH configuration in the system information (SI). The
NPRACH-ConfigSIGN-NB IEs and their respective field descriptions
are shown below:
TABLE-US-00001 NPRACH-ConfigSIB-NB information elements --
ASN1START NPRACH-ConfigSIB-NB-r13 ::= SEQUENCE {
nprach-CP-Length-r13 ENUMERATED {us66dot7, us266dot7},
rsrp-ThresholdsPrachInfoList-r13
RSRP-ThresholdsNPRACH-InfoList-NB-r13 OPTIONAL, -- need OR
nprach-ParametersList-r13 NPRACH-ParametersList-NB-r13 }
NPRACH-ParametersList-NB-r13 ::= SEQUENCE {SIZE (1..
maxNPRACH-Resources-NB-r13)} OF NPRACH-Parameters-NB-r13
NPRACH-Parameters-NB-r13::= SEQUENCE { nprach-Periodicity-r13
ENUMERATED {ms40, ms80, ms160, ms240, ms320, ms640, ms1280,
ms2560}, nprach-StartTime-r13 ENUMERATED {ms8, ms16, ms32, ms64,
ms128, ms256, ms512, ms1024}, nprach-SubcarrierOffset-r13
ENUMERATED {n0, n12, n24, n36, n2, n18, n34, spare1},
nprach-NumSubcarriers-r13 ENUMERATED {n12, n24, n36, n48},
nprach-SubcarrierMSG3-RangeStart-r13 ENUMERATED {zero, oneThird,
twoThird, one}, maxNumPreambleAttemptCE-r13 ENUMERATED {n3, n4, n5,
n6, n7, n8, n10, spare1}, numRepetitionsPerPreambleAttempt-r13
ENUMERATED {n1, n2, n4, n8, n16, n32, n64, n128},
npdcch-NumRepetitions-RA-r13 ENUMERATED {r1, r2, r4, r8, r16, r32,
r64, r128, r256, r512, r1024, r2048, spare4, spare3, spare2,
spare1}, npdcch-StartSF-CSS-RA-r13 ENUMERATED {v1dot5, v2, v4, v8,
v16, v32, v48, v64}, npdcch-Offset-RA-r13 ENUMERATED {zero,
oneEighth, oneFourth, threeEighth} }
RSRP-ThresholdsNPRACH-InfoList-NB-r13 ::= SEQUENCE {SIZE(1..2)} OF
RSRP-Range -- ASN1STOP
TABLE-US-00002 NPRACH-ConfigSIB-NB field descriptions
maxNumPreambleAttemptCE Maximum number of preamble transmission
attempts per NPRACH resource. See TS 36.321 [6].
npdcch-NumRepetitions-RA Maximum number of repetitions for NPDCCH
common search space (CSS) for RAR, Msg3 retransmission and Msg4,
see TS 36.211 [21]. npdcch-Offset -RA Fractional period offset of
starting subframe for NPDCCH common search space (CSS Type 2, see
TS 36.211 [21] and TS 36.213 [23]. npdcch-StartSF-CSS-RA Starting
subframe configuration for NPDCCH common search space (CSS),
including RAR, Msg3 retransmission, and Msg4, see TS 36.211 [21]
and TS 36.213 [23]. nprach-CP-Length Cyclic prefix length for
NPRACH transmission, see TS 36.211 [21, 5.2.1]. Value us66dot7
corresponds to 66.7 microseconds and value us266dot7 corresponds to
266.7 microseconds. nprach-NumSubcarriers Number of sub-carriers in
a NPRACH resource. In number of subcarriers nprach-ParametersList
Configures NPRACH parameters for each NPRACH resource. Up to three
PRACH resources can be configured in a cell. Each NPRACH resource
is associated with a different number of NPRACH repetitions.
nprach-Periodicity Periodicity of a NPRACH resource. Unit in
millisecond. nprach-StartTime Start time of the NPRACH resource in
one period. Unit in millisecond. nprach-SubcarrierOffset Frequency
location of the NPRACH resource. In number of subcarriers, offset
from sub-carrier 0. nprach-SubcarrierMSG3-RangeStart Fraction for
calculating the starting subcarrier index of the range reserved for
indication of UE support for multi-tone Msg3 transmission, within
the NPRACH resource.. Multi-tone Msg3 transmission is not supported
for {32, 64, 128} repetitions of NPRACH. For at least one of the
NPRACH resources with the number of NPRACH repetitions other than
{32, 64, 128}, the value of nprach-SubcarrierMSG3-RangeStart_should
be less than 1. numRepetitionPerPreambleAttempt Number of NPRACH
repetitions per attempt for each NPRACH resource, See TS 36.211
[21] rsrp-ThresholdsPrachInfoList The criterion for UEs to select a
NPRACH resource. Up to 2 RSRP threshold values can be signalled.
See TS 36.213 [23]. The first element corresponds to RSRP threshold
1, the second element corresponds to RSRP threshold 2. See TS
36.321 [6]. If absent, there is only one NPRACH resource.
SUMMARY
[0014] To address the foregoing problems with existing solutions,
disclosed is a method in a network node. The method comprises
reserving, within a Narrowband Physical Random Access Channel
(NPRACH) resource comprising a plurality of start subcarriers, a
subset of the plurality of start subcarriers for performing a
contention-free random access procedure. The method comprises
communicating, to one or more user equipment (UEs), information
indicating which of the plurality of start subcarriers within the
NPRACH resource are reserved for performing the contention-free
random access procedure.
[0015] In certain embodiments, the method may comprise
communicating, to a first UE, an instruction to use a particular
one of the reserved start subcarriers for performing the
contention-free random access procedure. In certain embodiments,
each of the plurality of start subcarriers within the NPRACH
resource may be a first subcarrier for a subcarrier hopping
sequence.
[0016] In certain embodiments, the information indicating which of
the plurality of start subcarriers within the NPRACH resource are
reserved for performing the contention-free random access procedure
may comprise a number of start subcarriers within the NPRACH
resource that are not reserved for performing the contention-free
random access procedure. The start subcarriers within the NPRACH
resource that are not reserved for performing the contention-free
random access procedure may be available for performing a
contention-based random access procedure. In certain embodiments,
the information may be signaled as part of a radio resource control
information element.
[0017] In certain embodiments, the information indicating which of
the plurality of start subcarriers within the NPRACH resource are
reserved for performing the contention-free random access procedure
may comprise a number of reserved start subcarriers.
[0018] According to another example embodiment, a network node is
disclosed. The network node comprises processing circuitry. The
processing circuitry is configured to reserve, within a Narrowband
Physical Random Access Channel (NPRACH) resource comprising a
plurality of start subcarriers, a subset of the plurality of start
subcarriers for performing a contention-free random access
procedure. The processing circuitry is configured to communicate,
to one or more user equipment (UEs), information indicating which
of the plurality of start subcarriers within the NPRACH resource
are reserved for performing the contention-free random access
procedure.
[0019] According to another example embodiment, a method in a user
equipment (UE) is disclosed. The method comprises receiving, from a
network node, information indicating which of a plurality of start
subcarriers within a Narrowband Physical Random Access Channel
(NPRACH) resource are reserved for performing a contention-free
random access procedure. The method comprises performing a random
access procedure based on the received information.
[0020] In certain embodiments, the start subcarriers that are
reserved for performing the contention-free random access procedure
may comprise a subset of the plurality of start subcarriers within
the NPRACH resource, and one or more start subcarriers that are not
in the reserved subset may be available for performing a
contention-based random access procedure. The information
indicating which of the plurality of start subcarriers within the
NPRACH resource are reserved for performing the contention-free
random access procedure may comprise a number of the one or more
start subcarriers that are not in the reserved subset. In certain
embodiments, the method may comprise determining which of the
plurality of start subcarriers are reserved for performing the
contention-free random access procedure based on the number of the
one or more start subcarriers that are not in the reserved subset.
In certain embodiments, the method may comprise selecting a first
start subcarrier from among the one or more start subcarriers that
are not in the reserved subset, and performing the random access
procedure based on the received information may comprise performing
a contention-based random access procedure using the selected first
start subcarrier.
[0021] In certain embodiments, the method may comprise receiving,
from the network node, an instruction to use a particular one of
the reserved start subcarriers for performing a contention-free
random access procedure, and performing the random access procedure
based on the received information may comprise performing the
contention-free random access procedure using the particular one of
the reserved start subcarriers.
[0022] In certain embodiments, the information indicating which of
the plurality of start subcarriers within the NPRACH resource are
reserved for performing the contention-free random access procedure
may comprise a number of reserved start subcarriers.
[0023] In certain embodiments, the information may be received in a
radio resource control information element. In certain embodiments,
each of the plurality of start subcarriers within the NPRACH
resource may be a first subcarrier for a subcarrier hopping
sequence.
[0024] Also disclosed is a user equipment (UE). The UE comprises
processing circuitry. The processing circuitry is configured to
receive, from a network node, information indicating which of a
plurality of start subcarriers within a Narrowband Physical Random
Access Channel (NPRACH) resource are reserved for performing a
contention-free random access procedure. The processing circuitry
is configured to perform a random access procedure based on the
received information.
[0025] Certain embodiments of the present disclosure may provide
one or more technical advantages. As one example, certain
embodiments may advantageously reduce signaling overhead and
resource inefficiencies. As another example, certain embodiments
may advantageously avoid over-provisioning and under-provisioning
of random access resources for new and old UEs, respectively. As
still another example, certain embodiments may advantageously avoid
the need to specify new RA-RNTI relations and/or a new random
access response format. Other advantages may be readily apparent to
one having skill in the art. Certain embodiments may have none,
some, or all of the recited advantages.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] For a more complete understanding of the disclosed
embodiments and their features and advantages, reference is now
made to the following description, taken in conjunction with the
accompanying drawings, in which:
[0027] FIG. 1 is a signal flow diagram of an example random access
procedure;
[0028] FIG. 2 illustrates an example embodiment of a wireless
communications network, in accordance with certain embodiments;
[0029] FIG. 3 illustrates a first example of how the NPRACH
resources can be reserved, in accordance with certain
embodiments;
[0030] FIG. 4 illustrates a second example of how the NPRACH
resources can be reserved, in accordance with certain
embodiments;
[0031] FIG. 5 illustrates a third example of how the NPRACH
resources can be reserved, in accordance with certain
embodiments;
[0032] FIG. 6 illustrates a fourth example of how the NPRACH
resources can be reserved, in accordance with certain
embodiments;
[0033] FIG. 7 illustrates a fifth example of how the NPRACH
resources can be reserved, in accordance with certain
embodiments;
[0034] FIG. 8 is a flow diagram of a method in a network node, in
accordance with certain embodiments;
[0035] FIG. 9 is a flow diagram of a method in a UE, in accordance
with certain embodiments;
[0036] FIG. 10 is a block schematic of an exemplary wireless
device, in accordance with certain embodiments;
[0037] FIG. 11 is a block schematic of an exemplary network node,
in accordance with certain embodiments;
[0038] FIG. 12 is a block schematic of an exemplary radio network
controller or core network node, in accordance with certain
embodiments;
[0039] FIG. 13 is a block schematic of an exemplary wireless
device, in accordance with certain embodiments; and
[0040] FIG. 14 is a block schematic of an exemplary network node,
in accordance with certain embodiments.
DETAILED DESCRIPTION
[0041] Release-13 NB-IoT supports contention-based random access
(i.e., requiring steps for contention resolution). To improve
efficiency, contention-free random access can be introduced in the
future. In contention-free random access, a preamble hopping
sequence can be assigned to a UE in a dedicated fashion. In some
cases, a dedicated preamble/subcarrier/preamble subcarrier hopping
sequence enables the steps of contention resolution to be omitted
and/or avoided since the network node (e.g., eNB) knows to which UE
the preamble/subcarrier/preamble subcarrier hopping sequence has
been assigned and can assume that an access attempt with this
preamble/subcarrier/preamble subcarrier is made by that UE. In some
cases of contention-free random access (in the NB-IoT context),
such as with Release-13 UEs, the one or more aspects of the
contention resolution procedure may still occur even though the UE
uses a dedicated preamble/subcarrier/preamble subcarrier hopping
sequence.
[0042] Since a Release-13 UE randomly selects one of the
preambles/subcarriers/preamble subcarrier hopping sequences of a
configured NPRACH, the preambles/subcarriers/preamble subcarrier
hopping sequences of an NPRACH configured with Release-13 signaling
cannot be used for contention-free access. This is because if a
preamble/subcarrier/preamble subcarrier hopping sequence of a
Release-13 NPRACH was assigned to a UE as a dedicated resource, the
network can no longer assume that an access attempt detected with
that preamble/subcarrier/preamble subcarrier hopping sequence is
made by the UE that was assigned that resource. Rather, the
detected access attempt may have been made by a Release-13 UE that
randomly selected the same resource.
[0043] New separate NPRACH resources would therefore need to be
defined/configured for the purpose of dedicated assignment and
contention-free random access. As a consequence, signaling overhead
(e.g., for providing the additional configuration) will increase.
As described above, NPRACH resources are provided in sets (i.e.,
chunks) of 12 subcarriers. Since contention-free random access is
more efficient than contention-based random access, fewer than 12
preambles/subcarriers/preamble subcarrier hopping sequences may be
needed. Also, because new resources will need to be
configured/indicated with new signaling that will not be
comprehended by a Release-13 UE, preambles/subcarriers/preamble
subcarrier hopping sequences that are not needed for
contention-free random access cannot be made available for
contention-based random access for Release-13 UEs. For example, if
only 5 out of 12 resources are needed for contention-free random
access, the remaining 7 resources cannot be made available to
Release-13 UEs for contention based random access since, in
Release-13, resources can only be made available in chunks of 12
resources and Release-13 UEs cannot comprehend new signaling (i.e.,
signaling introduced after the implementation of the UE). Thus,
resource usage will be inefficient due to over-provisioning for new
UEs and/or under-provisioning for old UEs, and trunking loss. In
addition, the introduction of a new/separate NPRACH may not be
compatible with Rel-13 RA-RNTI definition and/or random access
response format.
[0044] The present disclosure contemplates various embodiments that
may address these and other deficiencies associated with existing
approaches. For example, in certain embodiments, support for
contention-free preamble/subcarrier/preamble subcarrier hopping
sequence is provided by adding signaling of information indicating
how many subcarriers are reserved for contention-free random access
and rules for where these reserved subcarriers reside inside an
NPRACH resource. According to one example embodiment, a method in a
network node is disclosed. The network node reserves, within a
NPRACH resource comprising a plurality of start subcarriers, a
subset of the plurality of start subcarriers for performing a
contention-free random access procedure. The network node
communicates, to one or more UEs, information indicating which of
the plurality of start subcarriers within the NPRACH resource are
reserved for performing the contention-free random access
procedure.
[0045] In certain embodiments, the information indicating which of
the plurality of start subcarriers within the NPRACH resource are
reserved for performing the contention-free random access procedure
comprises a number of start subcarriers within the NPRACH resource
that are not reserved for performing the contention-free random
access procedure. The start subcarriers within the NPRACH resource
that are not reserved for performing the contention-free random
access procedure may be available for performing a contention-based
random access procedure. In certain embodiments, the information
indicating which of the plurality of start subcarriers within the
NPRACH resource are reserved for performing the contention-free
random access procedure may comprise a number of reserved start
subcarriers.
[0046] According to another example embodiment, a method in a UE is
disclosed. The UE receives, from a network node, information
indicating which of a plurality of start subcarriers within a
NPRACH resource are reserved for performing a contention-free
random access procedure. The UE performs a random access procedure
based on the received information. In certain embodiments, the
start subcarriers that are reserved for performing the
contention-free random access procedure may be a subset of the
plurality of start subcarriers within the NPRACH resource, and one
or more start subcarriers that are not in the reserved subset may
be available for performing a contention-based random access
procedure. In certain embodiments, the information indicating which
of the plurality of start subcarriers within the NPRACH resource
are reserved for performing the contention-free random access
procedure may comprise a number of the one or more start
subcarriers that are not in the reserved subset. In certain
embodiments, the information indicating which of the plurality of
start subcarriers within the NPRACH resource are reserved for
performing the contention-free random access procedure may comprise
a number of reserved start subcarriers.
[0047] Certain embodiments of the present disclosure may provide
one or more technical advantages. As one example, certain
embodiments may advantageously reduce signaling overhead and
resource inefficiencies. As another example, certain embodiments
may advantageously avoid over-provisioning and under-provisioning
of random access resources for new and old UEs, respectively. As
still another example, certain embodiments may advantageously avoid
the need to specify new RA-RNTI relations and/or a new random
access response format. Other advantages may be readily apparent to
one having skill in the art. Certain embodiments may have none,
some, or all of the recited advantages.
[0048] FIG. 2 is a block diagram illustrating an embodiment of a
network 100, in accordance with certain embodiments. Network 100
includes one or more UE(s) 110 (which may be interchangeably
referred to as wireless device(s) 110 or terminal(s) 110) and one
or more network node(s) 115 (which may be interchangeably referred
to as eNBs 115 or base stations 115). UEs 110 may communicate with
network nodes 115 over a wireless interface. For example, a UE 110
may transmit wireless signals to one or more of network nodes 115,
and/or receive wireless signals from one or more of network nodes
115. The wireless signals may contain voice traffic, data traffic,
control signals, and/or any other suitable information. In some
embodiments, an area of wireless signal coverage associated with a
network node 115 may be referred to as a cell 125. In some
embodiments, UEs 110 may have device-to-device (D2D) capability.
Thus, UEs 110 may be able to receive signals from and/or transmit
signals directly to another UE.
[0049] In certain embodiments, network nodes 115 may interface with
a radio network controller. The radio network controller may
control network nodes 115 and may provide certain radio resource
management functions, mobility management functions, and/or other
suitable functions. In certain embodiments, the functions of the
radio network controller may be included in network node 115. The
radio network controller may interface with a core network node. In
certain embodiments, the radio network controller may interface
with the core network node via an interconnecting network 120.
Interconnecting network 120 may refer to any interconnecting system
capable of transmitting audio, video, signals, data, messages, or
any combination of the preceding. Interconnecting network 120 may
include all or a portion of a public switched telephone network
(PSTN), a public or private data network, a local area network
(LAN), a metropolitan area network (MAN), a wide area network
(WAN), a local, regional, or global communication or computer
network such as the Internet, a wireline or wireless network, an
enterprise intranet, or any other suitable communication link,
including combinations thereof.
[0050] In some embodiments, the core network node may manage the
establishment of communication sessions and various other
functionalities for UEs 110. UEs 110 may exchange certain signals
with the core network node using the non-access stratum layer. In
non-access stratum signaling, signals between UEs 110 and the core
network node may be transparently passed through the radio access
network. In certain embodiments, network nodes 115 may interface
with one or more network nodes over an internode interface, such
as, for example, an X2 interface.
[0051] As described above, example embodiments of network 100 may
include one or more UEs 110, and one or more different types of
network nodes capable of communicating (directly or indirectly)
with UEs 110.
[0052] In some embodiments, the non-limiting term UE is used. UEs
110 described herein can be any type of wireless device capable of
communicating with network nodes 115 or another UE over radio
signals. UE 110 may also be a radio communication device, target
device, D2D UE, machine-type-communication (MTC) UE or UE capable
of machine to machine communication (M2M), low-cost and/or
low-complexity UE, sensor or actuator equipped with UE, tablet,
mobile terminal, smart phone, laptop embedded equipped (LEE),
laptop mounted equipment (LME), USB dongles, Customer Premises
Equipment (CPE), etc. UE 110 may operate under either normal
coverage or enhanced coverage with respect to its serving cell. The
enhanced coverage may be interchangeably referred to as extended
coverage. UE 110 may also operate in a plurality of coverage levels
(e.g., normal coverage, enhanced coverage level 1, enhanced
coverage level 2, enhanced coverage level 3 and so on). In some
cases, UE 110 may also operate in out-of-coverage scenarios.
[0053] Also, in some embodiments generic terminology, "network
node" is used. It can be any kind of network node, which may
comprise a base station (BS), radio base station, Node B, eNB, gNB,
multi-standard radio (MSR) radio node such as MSR BS, network
controller, radio network controller (RNC), base station controller
(BSC), relay node, relay donor node controlling relay, base
transceiver station (BTS), access point (AP), radio access point,
transmission points, transmission nodes, Remote Radio Unit (RRU),
Remote Radio Head (RRH), nodes in distributed antenna system (DAS),
Multi-cell/multicast Coordination Entity (MCE), core network node
(e.g., MSC, MME, etc.), O&M, OSS, SON, positioning node (e.g.,
E-SMLC), MDT, or any other suitable network node.
[0054] The terminology such as network node and UE should be
considered non-limiting and does in particular not imply a certain
hierarchical relation between the two; in general "eNodeB" could be
considered as device 1 and "UE" device 2, and these two devices
communicate with each other over some radio channel.
[0055] Example embodiments of UE 110, network nodes 115, and other
network nodes (such as radio network controller or core network
node) are described in more detail below with respect to FIGS.
10-14.
[0056] Although FIG. 2 illustrates a particular arrangement of
network 100, the present disclosure contemplates that the various
embodiments described herein may be applied to a variety of
networks having any suitable configuration. For example, network
100 may include any suitable number of UEs 110 and network nodes
115, as well as any additional elements suitable to support
communication between UEs or between a UE and another communication
device (such as a landline telephone). Furthermore, although
certain embodiments may be described as implemented in a NB-IoT
network, the embodiments may be implemented in any appropriate type
of telecommunication system supporting any suitable communication
standards (including 5G standards) and using any suitable
components, and are applicable to any radio access technology (RAT)
or multi-RAT systems in which a UE receives and/or transmits
signals (e.g., data). For example, the various embodiments
described herein may be applicable to NB-IoT, New Radio (NR), Long
Term Evolution (LTE), LTE-Advanced, 5G, UMTS, HSPA, GSM, cdma2000,
WCDMA, WiMax, UMB, WiFi, another suitable radio access technology,
or any suitable combination of one or more radio access
technologies. Although certain embodiments may be described in the
context of wireless transmissions in the downlink, the present
disclosure contemplates that the various embodiments are equally
applicable in the uplink.
[0057] As described above, since a Release-13 UE randomly chooses
one of the preambles/subcarriers/preamble subcarrier hopping
sequences of a configured NPRACH, the
preambles/subcarriers/preamble subcarrier hopping sequences of an
NPRACH configured with Release-13 signaling cannot be used for
contention-free random access. This is because if a
preamble/subcarrier/preamble subcarrier hopping sequence of a
Release-13 NPRACH were assigned to a UE as a dedicated resource,
the network cannot assume that an access attempt detected with that
preamble/subcarrier/preamble subcarrier hopping sequence is made by
the UE that was assigned that resource. Rather, it is possible that
the detected access attempt may have been made by a Release-13 UE
that randomly selected the same resource. These problems can be
avoided by enabling reservation of some subcarriers in the
current/early release (e.g., Release-13) such that these resources
are not used for contention-based random access by UEs of the
current/early release (e.g., Release-13).
[0058] In the descriptions of FIGS. 3-7 below, the prefixes
"nprach-" and postfix "-r13" from the existing IE description in
section 2.1 and R2-164573 have been removed to simplify the
figures.
[0059] FIG. 3 illustrates a first example of how the NPRACH
resources can be reserved, in accordance with certain embodiments.
More particularly, FIG. 3 illustrates an example of how the NPRACH
resources can be reserved in a scenario in which no
single/multi-tone Msg3 partitions are used. In FIG. 3, the 48
different subcarriers (indexes 0-47) are shown on the y-axis. The
subcarrier spacing is 3.75 kHz (i.e., the total bandwidth is
48*3.75=180 kHz for a NB-IoT cell). These subcarriers may be
interchangeably referred to herein as start subcarriers.
[0060] In the example of FIG. 3, NPRACH resource 305 is indicated
by a rectangle covering a set of subcarriers. As noted above, no
single/multi-tone Msg3 partitions are used, so in this example
NPRACH resource 305 is a single partition (in contrast to the
examples of FIGS. 5 and 7, described in more detail below). NPRACH
resource 305 is divided into a reserved set of subcarriers 310 and
a set of subcarriers 315 that are not reserved. Reserved set of
subcarriers 310 have been reserved (for example, by a network node
such as network node 115 described above in relation to FIG. 2) for
performing a contention-free random access procedure. Reserved set
of subcarriers 310 is graphically represented inside the rectangle
of NPRACH resource 305 by an upward diagonal pattern. The
subcarriers in the set of subcarriers 315 that are not reserved for
a contention-free random access procedure are available for
performing a contention-based random access procedure (e.g., by a
Release-13 UE).
[0061] In certain embodiments, the network node may communicate
information indicating which of the plurality of start subcarriers
within NPRACH resource 305 are reserved for performing the
contention-free random access procedure. The information indicating
which of the plurality of start subcarriers within NPRACH resource
305 are reserved for performing the contention-free random access
procedure may be communicated in any suitable manner. For example,
in certain embodiments the information may be signaled as part of a
radio resource control (RRC) IE. The information indicating which
of the plurality of start subcarriers within NPRACH resource 305
are reserved for performing the contention-free random access
procedure may be any suitable information.
[0062] In the example embodiment of FIG. 3, the information
indicating which of the plurality of start subcarriers within
NPRACH resource 305 are reserved for performing the contention-free
random access procedure may comprise a number of start subcarriers
within NPRACH resource 305 that are not reserved for performing the
contention-free random access procedure. In other words, the
communicated information may be a number of start subcarriers in
the subset of start subcarriers 315 that are not reserved for a
contention-free random access procedure. In such a scenario, a UE
(such as UE 110 described above in relation to FIG. 2) may be aware
of the start subcarriers included in NPRACH resource 305. When such
a UE receives the information regarding the subset of start
subcarriers 315 that are not reserved for the contention-free
random access procedure, the UE is able to determine which of the
plurality of start subcarriers within NPRACH resource 305 are
reserved for performing the contention-free random access procedure
(e.g., subset of start subcarriers 310).
[0063] As described above, the information may be communicated as a
RRC IE. In a scenario in which the information communicated to the
UE is a number of the one or more start subcarriers 315 that are
not in the reserved subset, the IE may be, for example, an
nprach-NumCBRA-StartSubcarriers IE. The
nprach-NumCBRA-StartSubcarriers IE may indicate the number of start
subcarriers from which a UE can randomly select a start subcarrier
for a contention-based random access procedure. In some cases, the
start subcarrier indices in this subset that the UE is allowed to
randomly select from may be given by nprach-SubcarrierOffset+[0,
nprach-NumCBRA-StartSubcarriers-1].
[0064] The UE that receives the information indicating which of the
plurality of start subcarriers within NPRACH resource 305 are
reserved for performing a contention-free random access procedure
may perform a random access procedure based on the received
information. The type of random access procedure performed by the
UE may depend on the capabilities of the UE. For example, if the UE
is capable of performing a contention-free random access procedure,
the UE may be assigned a start subcarrier from the reserved set of
start subcarriers 310 that the UE should use for the
contention-free random access procedure. In some cases, the UE may
receive, from the network node, an instruction to use a particular
one of the reserved start subcarriers for performing the
contention-free random access procedure. If the UE is not capable
of performing a contention-free random access procedure, the UE may
select (e.g., randomly or based on one or more criteria) a first
start subcarrier from among the one or more start subcarriers 315
that are not reserved for a contention-free random access
procedure. In such a scenario, the UE may perform a
contention-based random access procedure using the selected first
start subcarrier.
[0065] Thus, in this example the number of non-reserved start
subcarriers that may be used for contention-based random access is
signalled to the UE. This information indicates to the UE that the
remaining start subcarriers which may not be used for
contention-based random access are reserved for contention-free
random access. An alternative approach in which the number of
reserved start subcarriers is signalled (i.e., instead of
signalling the number of non-reserved start subcarriers the number
of reserved start subcarriers is signalled) is described below in
relation to FIGS. 4 and 5.
[0066] FIG. 4 illustrates a second example of how the NPRACH
resources can be reserved, in accordance with certain embodiments.
More particularly, FIG. 4 illustrates how the NPRACH resources can
be reserved in a scenario in which no single/multi-tone Msg3
partitions are used. Similar to FIG. 3 described above, the 48
different subcarriers (index is 0-47) are shown on the y-axis. The
subcarrier spacing is 3.75 kHz (i.e., the total bandwidth is
48*3.75=180 kHz for a NB-IoT cell).
[0067] In the example of FIG. 4, NPRACH resource 405 is indicated
by a rectangle covering a set of subcarriers. As noted above, no
single/multi-tone Msg3 partitions are used, so in this example
NPRACH resource 405 is a single partition (in contrast to the
examples of FIGS. 5 and 7, described in more detail below). NPRACH
resource 405 is divided into a reserved set of subcarriers 410 and
a set of subcarriers 415 that are not reserved. Reserved set of
subcarriers 410 have been reserved (for example, by a network node
such as network node 115 described above in relation to FIG. 2) for
performing a contention-free random access procedure. Reserved set
of subcarriers 410 is graphically represented inside the rectangle
of NPRACH resource 405 by an upward diagonal pattern. The
subcarriers in the set of subcarriers 415 that are not reserved for
a contention-free random access procedure are available for
performing a contention-based random access procedure (e.g., by a
Release-13 UE).
[0068] As described above, the network node (such as network node
115 described above in relation to FIG. 2) may communicate
information indicating which of the plurality of start subcarriers
within NPRACH resource 405 are reserved for performing the
contention-free random access procedure. The information indicating
which of the plurality of start subcarriers within NPRACH resource
405 are reserved for performing the contention-free random access
procedure may be communicated in any suitable manner. For example,
in certain embodiments the information may be signaled as part of a
RRC IE. The information indicating which of the plurality of start
subcarriers within NPRACH resource 405 are reserved for performing
the contention-free random access procedure may be any suitable
information.
[0069] In the example of FIG. 4, the information indicating which
of the plurality of start subcarriers within NPRACH resource 405
are reserved for performing the contention-free random access
procedure may comprise a number of reserved start subcarriers 410.
In such a scenario, a new IE called NumReservedStartSubcarrier is
added to indicate the number of start subcarriers that are reserved
for contention-free random access. In certain embodiments, the
number of start subcarriers is taken from the upper edge of NPRACH
resource 405 (i.e., starting from the last index within the
interval [0, NumSubcarriers-1]). A detailed proposal of the
additional RRC IE is illustrated below compared to section 2.1 and
R2-164573 included in the NPRACH-Parameters-NB-r13. The new added
IE is called nprach-NumReservedStartSubcarriers-r13 and is put in
italic and underlined to highlight the change compared to section
2.1 and R2-164573. The field description for this new parameter is
also provided, including the rule for how to determine the
subcarriers that are reserved (similar to what is shown in FIG.
4).
TABLE-US-00003 NPRACH-Parameters-NB-r13 ::= SEQUENCE {
nprach-Periodicity-r13 ENUMERATED {ms40, ms80, ms160, ms240, ms320,
ms640, ms1280, ms2560}, nprach-StartTime-r13 ENUMERATED {ms8, ms16,
ms32, ms64, ms128, ms256, ms512, ms1024},
nprach-SubcarrierOffset-r13 ENUMERATED {n0, n12, n24, n36, n2, n18,
n34, spare1}, nprach-NumSubcarriers-r13 ENUMERATED {n12, n24, n36,
n48}, nprach-SubcarrierMSG3-RangeStart-r13 ENUMERATED {zero,
oneThird, twoThird, one}, nprach-NumReservedStartSubcarriers-r13
ENUMERATED {n0, n1, n2, n3, n4, n6, n8, n12},
maxNumPreambleAttemptCE-r13 ENUMERATED {n3, n4, n5, n6, n7, n8,
n10, spare1}, numRepetitionsPerPreambleAttempt-r13 ENUMERATED {n1,
n2, n4, n8, n16, n32, n64, n128}, npdcch-NumRepetitions-RA-r13
ENUMERATED {r1, r2, r4, r8, r16, r32, r64, r128, r256, r512, r1024,
r2048, spare4, spare3, spare2, spare1}, npdcch-StartSF-CSS-RA-r13
ENUMERATED {v1dot5, v2, v4, v8, v16, v32, v48, v64},
npdcch-Offset-RA-r13 ENUMERATED {zero, oneEighth, oneFourth,
threeEighth} }
TABLE-US-00004 NPRACH-ConfigSIB-NB field descriptions . . .
nprach-NumReservedStartSubcarriers: The number of start subcarriers
reserved for contention free random access. The UE shall not select
one of these reserved start subcarriers when randomly selecting a
start subcarrier in the preamble selection in 36.321. The start
subcarrier indexes that the UE is allowed to randomly select from
are according to the following: If nprach-SubcarrierMSG3-RangeStart
is equal to {zero} or {one}: nprach-SubcarrierOffset +[0,
nprach-NumSubcarriers - nprach-NumReservedStartSubcarriers - 1];
else if nprach-SubcarrierMSG3-RangeStart is equal to {oneThird} or
{twoThird}: (nprach-SubcarrierOffset +[0, nprach-NumSubcarriers*
nprach-SubcarrierMSG3-RangeStart -
CEILING(nprach-NumReservedStartSubcarriers/2) - 1] for the
single-tone Msg3 NPRACH partition; nprach-SubcarrierOffset
+[nprach-NumSubcarriers* nprach-SubcarrierMSG3-RangeStart, nprach-
NumSubcarriers - FLOOR(nprach-NumReservedStartSubcarriers/2) - 1]
for the multi-tone Msg3 NPRACH partition; . . .
[0070] The UE that receives the information indicating which of the
plurality of start subcarriers within NPRACH resource 405 are
reserved for performing a contention-free random access procedure
may perform a random access procedure based on the received
information. For example, if the UE is capable of performing a
contention-free random access procedure, the UE may be assigned a
start subcarrier from the reserved set of start subcarriers 410
that the UE should use for the contention-free random access
procedure. In some cases, the UE may receive, from the network
node, an instruction to use a particular one of the reserved start
subcarriers for performing the contention-free random access
procedure. The UE may then perform the contention-free random
access procedure. In some cases (e.g., with Release-14 UEs), the
contention-free random access procedure may no longer require the
contention-resolution procedure described above in relation to FIG.
1. In some cases (e.g., with Release-13 UEs), one or more steps of
the contention-resolution procedure may still be performed, despite
the random access procedure being essentially contention-free.
[0071] If the UE is not capable of performing a contention-free
random access procedure, the UE may select (e.g., randomly or based
on one or more criteria) a first start subcarrier from among the
one or more start subcarriers 415 that are not reserved for a
contention-free random access procedure. In such a scenario, the UE
may perform a contention-based random access procedure using the
selected first start subcarrier.
[0072] FIG. 5 illustrates a third example of how the NPRACH
resources can be reserved, in accordance with certain embodiments.
More particularly, FIG. 5 illustrates an example of how NPRACH
resources 505 can be reserved in a scenario in which
single/multi-tone Msg3 partitions are used. In such a scenario,
NPRACH resource 505 is partitioned into two sets, a first set 510
for single-tone and a second set 515 for multi-tone Msg3
transmission. Within each partition 510 and 515, a subset of the
start subcarriers are reserved for performing a contention-free
random access procedure. As shown in FIG. 5, first set 510 includes
a subset of start subcarriers 520 that are reserved for a
contention-free random access procedure and a subset of start
subcarriers 525 that are not reserved for a contention-free random
access procedure and are therefore available for performing a
contention-based random access procedure. Similarly, second set 515
includes a subset of start subcarriers 530 that are reserved for a
contention-free random access procedure and a subset of start
subcarriers 535 that are not reserved for a contention-free random
access procedure and are therefore available for performing a
contention-based random access procedure.
[0073] As described above, a network node (such as network node 115
described above in relation to FIG. 2) may communicate information
indicating which of the plurality of start subcarriers within
NPRACH resource 505 are reserved for performing the contention-free
random access procedure (for example, in a RRC IE such as the
NumCBRA-StartSubcarriers IE described above in relation to FIG. 3
or the NumReservedStartSubcarrier IE described above in relation to
FIG. 4). Although FIG. 5 illustrates an example in which the
NumReservedStartSubcarrier IE element is used, the present
disclosure is not limited to such an example embodiment. Rather,
the present disclosure contemplates that in certain embodiments the
NumCBRA-StartSubcarriers IE, or any other suitable information
element, may be used.
[0074] In a scenario such as the one illustrated in FIG. 5 in which
single/multi-tone Msg3 partitions are used, one or more rules may
be defined to enable a UE that receives the
NumReservedStartSubcarrier IE to determine how many start
subcarriers in each of partitions 510 and 515 are reserved for
performing a contention-free random access procedure. In certain
embodiments, the rule may use the floor( ) and ceiling( ) function
for calculating the number of reserved start subcarriers per
partition (in the example of FIG. 5 the mathematical operators for
these functions are shown as .left brkt-bot. .right brkt-bot. and
.left brkt-top. .right brkt-bot., respectively. In certain
embodiments, the following rules may apply. If the number of
reserved subcarriers (e.g., as indicated by the
NumReservedStartSubcarrier IE) is an even number, then each of
partitions 510 and 515 get an equal amount of reserved subcarriers.
If the number of reserved subcarriers is an odd number, then the
first partition (e.g., partition 510) gets one more reserved
subcarrier compared to the second partition (e.g., partition 515).
If only one subcarrier is reserved, then the second partition
(e.g., partition 515) of NPRACH resource 505 will not have any
reserved subcarriers.
[0075] In certain embodiments, second partition 515 could get one
more reserved subcarrier in case the floor( ) and ceiling( )
functions change places. If any such change would be done, the IE
will be the same as described herein but the field descriptions
above would need to be modified.
[0076] FIG. 6 illustrates a fourth example of how the NPRACH
resources can be reserved, in accordance with certain embodiments.
The example embodiment of FIG. 6 is similar to the example
embodiment of FIG. 4 in that NPRACH resource 605 is indicated by a
rectangle covering a set of subcarriers. Like the example
embodiment of FIG. 4, no single/multi-tone Msg3 partitions are
used, so in this example NPRACH resource 605 is a single partition
divided into a reserved set of subcarriers 610 that are reserved
for a contention-free random access procedure and a set of
subcarriers 615 that are not reserved and are therefore available
for a contention-based random access procedure. In contrast to the
example embodiment described above in relation to FIG. 4, FIG. 6
illustrates a scenario in which the reserved start subcarriers 610
are started from the lower edge of NPRACH partition 605.
[0077] FIG. 7 illustrates a fifth example of how the NPRACH
resources can be reserved, in accordance with certain embodiments.
The example embodiment of FIG. 7 is similar to the example
embodiment of FIG. 5 in that FIG. 7 illustrates how NPRACH
resources 705 can be reserved in a scenario in which
single/multi-tone Msg3 partitions are used. In such a scenario,
NPRACH resource 705 is partitioned into two sets, a first set 710
for single-tone and a second set 715 for multi-tone Msg3
transmission. Within each partition, a subset of the start
subcarriers are reserved for performing a contention-free random
access procedure. As shown in FIG. 7, first set 710 includes a
subset of start subcarriers 720 that are reserved for a
contention-free random access procedure and a subset of start
subcarriers 725 that are not reserved for a contention-free random
access procedure and are therefore available for performing a
contention-based random access procedure. Similarly, second set 715
includes a subset of start subcarriers 730 that are reserved for a
contention-free random access procedure and a subset of start
subcarriers 735 that are not reserved for a contention-free random
access procedure and are therefore available for performing a
contention-based random access procedure.
[0078] In contrast to the example embodiment described above in
relation to FIG. 5, FIG. 7 illustrates a scenario in which the
reserved start subcarriers 720 and 730 are started from the lower
edge of NPRACH partitions 710 and 715, respectively. A UE may
determine how many start subcarriers in each of partitions 710 and
715 are reserved for performing a contention-free random access
procedure in the manner described above in connection with FIG. 5.
In certain embodiments, the second partition could get one more
reserved subcarrier in case the floor( ) and ceiling( ) functions
change places. If any such change would be done, the IE will be the
same but the field description would need to be updated slightly
compared to the above.
[0079] Although the above embodiments describe the use of the
reserved start subcarriers for contention-free random access
scenarios, there should not be any limitation in the system for the
network node (e.g., eNB) to provide the same reserved start
subcarrier to multiple UEs at the same time in order to obtain
"reduced contention probability" for other use cases. The present
disclosure contemplates that the various embodiments described
herein may be applicable to a variety of use cases.
[0080] FIG. 8 is a flow diagram of a method 800 in a network node,
in accordance with certain embodiments. Method 800 begins at step
804, where the network node reserves, within a NPRACH resource
comprising a plurality of start subcarriers, a subset of the
plurality of start subcarriers for performing a contention-free
random access procedure. In certain embodiments, each of the
plurality of start subcarriers within the NPRACH resource may be a
first subcarrier for a subcarrier hopping sequence.
[0081] At step 808, the network node communicates, to one or more
UEs, information indicating which of the plurality of start
subcarriers within the NPRACH resource are reserved for performing
the contention-free random access procedure. In certain
embodiments, the information may be signaled as part of a radio
resource control information element.
[0082] In certain embodiments, the information indicating which of
the plurality of start subcarriers within the NPRACH resource are
reserved for performing the contention-free random access procedure
may comprise a number of start subcarriers within the NPRACH
resource that are not reserved for performing the contention-free
random access procedure. The start subcarriers within the NPRACH
resource that are not reserved for performing the contention-free
random access procedure may be available for performing a
contention-based random access procedure.
[0083] In certain embodiments, the information indicating which of
the plurality of start subcarriers within the NPRACH resource are
reserved for performing the contention-free random access procedure
may comprise a number of reserved start subcarriers. In certain
embodiments, the method may comprise communicating, to a first UE,
an instruction to use a particular one of the reserved start
subcarriers for performing the contention-free random access
procedure.
[0084] FIG. 9 is a flow diagram of a method 900 in a UE, in
accordance with certain embodiments. Method 900 begins at step 904,
where the UE receives, from a network node, information indicating
which of a plurality of start subcarriers within a NPRACH resource
are reserved for performing a contention-free random access
procedure. In certain embodiments, the start subcarriers that are
reserved for performing the contention-free random access procedure
may comprise a subset of the plurality of start subcarriers within
the NPRACH resource. One or more start subcarriers that are not in
the reserved subset may be available for performing a
contention-based random access procedure. In certain embodiments,
each of the plurality of start subcarriers within the NPRACH
resource is a first subcarrier for a subcarrier hopping sequence.
In certain embodiments, the information may be received in a radio
resource control information element.
[0085] At step 908, the UE performs a random access procedure based
on the received information.
[0086] In certain embodiments, the information indicating which of
the plurality of start subcarriers within the NPRACH resource are
reserved for performing the contention-free random access procedure
may comprise a number of the one or more start subcarriers that are
not in the reserved subset. The method may comprise determining
which of the plurality of start subcarriers are reserved for
performing the contention-free random access procedure based on the
number of the one or more start subcarriers that are not in the
reserved subset. The method may comprise selecting a first start
subcarrier from among the one or more start subcarriers that are
not in the reserved subset. In such a scenario, performing the
random access procedure based on the received information may
comprise performing a contention-based random access procedure
using the selected first start subcarrier.
[0087] In certain embodiments, the information indicating which of
the plurality of start subcarriers within the NPRACH resource are
reserved for performing the contention-free random access procedure
may comprise a number of reserved start subcarriers.
[0088] In certain embodiments, the method may comprise receiving,
from the network node, an instruction to use a particular one of
the reserved start subcarriers for performing a contention-free
random access procedure. In such a scenario, performing the random
access procedure based on the received information may comprise
performing the contention-free random access procedure using the
particular one of the reserved start subcarriers.
[0089] FIG. 10 is a block schematic of an exemplary UE 110, in
accordance with certain embodiments. UE 110 may refer to any type
of wireless device communicating with a node and/or with another
wireless device in a cellular or mobile communication system.
Examples of UE 110 include a mobile phone, a smart phone, a PDA
(Personal Digital Assistant), a portable computer (e.g., laptop,
tablet), a sensor, an actuator, a modem, a
machine-type-communication (MTC) device/machine-to-machine (M2M)
device, laptop embedded equipment (LEE), laptop mounted equipment
(LME), USB dongles, a D2D capable device, or another device that
can provide wireless communication. A UE 110 may also be referred
to as a wireless device, a station (STA), a device, or a terminal
in some embodiments. UE 110 includes transceiver 1010, processing
circuitry 1020, and memory 1030. In some embodiments, transceiver
1010 facilitates transmitting wireless signals to and receiving
wireless signals from network node 115 (e.g., via antenna 1040),
processing circuitry 1020 executes instructions to provide some or
all of the functionality described above as being provided by UE
110, and memory 1030 stores the instructions executed by processing
circuitry 1020.
[0090] Processing circuitry 1020 may include any suitable
combination of hardware and software implemented in one or more
modules to execute instructions and manipulate data to perform some
or all of the described functions of UE 110, such as the functions
of UE 110 described above in relation to FIGS. 1-9. In some
embodiments, processing circuitry 1020 may include, for example,
one or more computers, one or more central processing units (CPUs),
one or more microprocessors, one or more applications, one or more
application specific integrated circuits (ASICs), one or more field
programmable gate arrays (FPGAs) and/or other logic.
[0091] Memory 1030 is generally operable to store instructions,
such as a computer program, software, an application including one
or more of logic, rules, algorithms, code, tables, etc. and/or
other instructions capable of being executed by processing
circuitry 1020. Examples of memory 1030 include computer memory
(for example, Random Access Memory (RAM) or Read Only Memory
(ROM)), mass storage media (for example, a hard disk), removable
storage media (for example, a Compact Disk (CD) or a Digital Video
Disk (DVD)), and/or or any other volatile or non-volatile,
non-transitory computer-readable and/or computer-executable memory
devices that store information, data, and/or instructions that may
be used by processing circuitry 1020.
[0092] Other embodiments of UE 110 may include additional
components beyond those shown in FIG. 10 that may be responsible
for providing certain aspects of the wireless device's
functionality, including any of the functionality described above
and/or any additional functionality (including any functionality
necessary to support the solution described above). As just one
example, UE 110 may include input devices and circuits, output
devices, and one or more synchronization units or circuits, which
may be part of the processing circuitry 1020. Input devices include
mechanisms for entry of data into UE 110. For example, input
devices may include input mechanisms, such as a microphone, input
elements, a display, etc. Output devices may include mechanisms for
outputting data in audio, video and/or hard copy format. For
example, output devices may include a speaker, a display, etc.
[0093] FIG. 11 is a block schematic of an exemplary network node
115, in accordance with certain embodiments. Network node 115 may
be any type of radio network node or any network node that
communicates with a UE and/or with another network node. Examples
of network node 115 include an eNodeB, a gNB, a node B, a base
station, a wireless access point (e.g., a Wi-Fi access point), a
low power node, a base transceiver station (BTS), relay, donor node
controlling relay, transmission points, transmission nodes, remote
RF unit (RRU), remote radio head (RRH), multi-standard radio (MSR)
radio node such as MSR BS, nodes in distributed antenna system
(DAS), O&M, OSS, SON, positioning node (e.g., E-SMLC), MDT, or
any other suitable network node. Network nodes 115 may be deployed
throughout network 100 as a homogenous deployment, heterogeneous
deployment, or mixed deployment. A homogeneous deployment may
generally describe a deployment made up of the same (or similar)
type of network nodes 115 and/or similar coverage and cell sizes
and inter-site distances. A heterogeneous deployment may generally
describe deployments using a variety of types of network nodes 115
having different cell sizes, transmit powers, capacities, and
inter-site distances. For example, a heterogeneous deployment may
include a plurality of low-power nodes placed throughout a
macro-cell layout. Mixed deployments may include a mix of
homogenous portions and heterogeneous portions.
[0094] Network node 115 may include one or more of transceiver
1110, processing circuitry 1120, memory 1130, and network interface
1140. In some embodiments, transceiver 1110 facilitates
transmitting wireless signals to and receiving wireless signals
from UE 110 (e.g., via antenna 1150), processing circuitry 1120
executes instructions to provide some or all of the functionality
described above as being provided by a network node 115, memory
1130 stores the instructions executed by processing circuitry 1120,
and network interface 1140 communicates signals to backend network
components, such as a gateway, switch, router, Internet, Public
Switched Telephone Network (PSTN), core network nodes or radio
network controllers 130, etc.
[0095] Processing circuitry 1120 may include any suitable
combination of hardware and software implemented in one or more
modules to execute instructions and manipulate data to perform some
or all of the described functions of network node 115, such as
those described above in relation to FIGS. 1-9. In some
embodiments, processing circuitry 1120 may include, for example,
one or more computers, one or more central processing units (CPUs),
one or more microprocessors, one or more applications, and/or other
logic.
[0096] Memory 1130 is generally operable to store instructions,
such as a computer program, software, an application including one
or more of logic, rules, algorithms, code, tables, etc. and/or
other instructions capable of being executed by processing
circuitry 1120. Examples of memory 1130 include computer memory
(for example, Random Access Memory (RAM) or Read Only Memory
(ROM)), mass storage media (for example, a hard disk), removable
storage media (for example, a Compact Disk (CD) or a Digital Video
Disk (DVD)), and/or or any other volatile or non-volatile,
non-transitory computer-readable and/or computer-executable memory
devices that store information.
[0097] In some embodiments, network interface 1140 is
communicatively coupled to processing circuitry 1120 and may refer
to any suitable device operable to receive input for network node
115, send output from network node 115, perform suitable processing
of the input or output or both, communicate to other devices, or
any combination of the preceding. Network interface 1140 may
include appropriate hardware (e.g., port, modem, network interface
card, etc.) and software, including protocol conversion and data
processing capabilities, to communicate through a network.
[0098] Other embodiments of network node 115 may include additional
components beyond those shown in FIG. 11 that may be responsible
for providing certain aspects of the radio network node's
functionality, including any of the functionality described above
and/or any additional functionality (including any functionality
necessary to support the solutions described above). The various
different types of network nodes may include components having the
same physical hardware but configured (e.g., via programming) to
support different radio access technologies, or may represent
partly or entirely different physical components.
[0099] FIG. 12 is a block schematic of an exemplary radio network
controller or core network node 130, in accordance with certain
embodiments. Examples of network nodes can include a mobile
switching center (MSC), a serving GPRS support node (SGSN), a
mobility management entity (MME), a radio network controller (RNC),
a base station controller (BSC), and so on. The radio network
controller or core network node 130 includes processing circuitry
1220, memory 1230, and network interface 1240. In some embodiments,
processing circuitry 1220 executes instructions to provide some or
all of the functionality described above as being provided by the
network node, memory 1230 stores the instructions executed by
processing circuitry 1220, and network interface 1240 communicates
signals to any suitable node, such as a gateway, switch, router,
Internet, Public Switched Telephone Network (PSTN), network nodes
115, radio network controllers or core network nodes 130, etc.
[0100] Processing circuitry 1220 may include any suitable
combination of hardware and software implemented in one or more
modules to execute instructions and manipulate data to perform some
or all of the described functions of the radio network controller
or core network node 130. In some embodiments, processing circuitry
1220 may include, for example, one or more computers, one or more
central processing units (CPUs), one or more microprocessors, one
or more applications, and/or other logic.
[0101] Memory 1230 is generally operable to store instructions,
such as a computer program, software, an application including one
or more of logic, rules, algorithms, code, tables, etc. and/or
other instructions capable of being executed by processing
circuitry 1220. Examples of memory 1230 include computer memory
(for example, Random Access Memory (RAM) or Read Only Memory
(ROM)), mass storage media (for example, a hard disk), removable
storage media (for example, a Compact Disk (CD) or a Digital Video
Disk (DVD)), and/or or any other volatile or non-volatile,
non-transitory computer-readable and/or computer-executable memory
devices that store information.
[0102] In some embodiments, network interface 1240 is
communicatively coupled to processing circuitry 1220 and may refer
to any suitable device operable to receive input for the network
node, send output from the network node, perform suitable
processing of the input or output or both, communicate to other
devices, or any combination of the preceding. Network interface
1240 may include appropriate hardware (e.g., port, modem, network
interface card, etc.) and software, including protocol conversion
and data processing capabilities, to communicate through a
network.
[0103] Other embodiments of the network node may include additional
components beyond those shown in FIG. 12 that may be responsible
for providing certain aspects of the network node's functionality,
including any of the functionality described above and/or any
additional functionality (including any functionality necessary to
support the solution described above).
[0104] FIG. 13 is a schematic block diagram of an exemplary
wireless device, in accordance with certain embodiments. UE 110 may
include one or more modules. For example, UE 110 may include a
determining module 1310, a communication module 1320, a receiving
module 1330, an input module 1340, a display module 1350, and any
other suitable modules. In some embodiments, one or more of
determining module 1310, communication module 1320, receiving
module 1330, input module 1340, display module 1350, or any other
suitable module may be implemented using one or more processors,
such as processing circuitry 1020 described above in relation to
FIG. 10. In certain embodiments, the functions of two or more of
the various modules may be combined into a single module. UE 110
may perform the methods for providing contention free random access
resources for NB-IoT described above in relation to FIGS. 1-9.
[0105] Determining module 1310 may perform the processing functions
of UE 110. For example, determining module 1310 may perform a
random access procedure based on the received information. As
another example, determining module 1310 may determine which of the
plurality of start subcarriers are reserved for performing the
contention-free random access procedure based on the number of the
one or more start subcarriers that are not in the reserved subset.
As still another example, determining module 1310 may select a
first start subcarrier from among the one or more start subcarriers
that are not in the reserved subset. Determining module 1310 may
include or be included in one or more processors, such as
processing circuitry 1020 described above in relation to FIG. 10.
Determining module 1310 may include analog and/or digital circuitry
configured to perform any of the functions of determining module
1310 and/or processing circuitry 1020 described above. The
functions of determining module 1310 described above may, in
certain embodiments, be performed in one or more distinct
modules.
[0106] Communication module 1320 may perform the transmission
functions of UE 110. Communication module 1320 may include a
transmitter and/or a transceiver, such as transceiver 1010
described above in relation to FIG. 10. Communication module 1320
may include circuitry configured to wirelessly transmit messages
and/or signals. In particular embodiments, communication module
1320 may receive messages and/or signals for transmission from
determining module 1310. In certain embodiments, the functions of
communication module 1320 described above may be performed in one
or more distinct modules.
[0107] Receiving module 1330 may perform the receiving functions of
UE 110. For example, receiving module 1330 may receive, from a
network node, information indicating which of a plurality of start
subcarriers within a Narrowband Physical Random Access Channel
(NPRACH) resource are reserved for performing a contention-free
random access procedure. As another example, receiving module 1330
may receive, from the network node, an instruction to use a
particular one of the reserved start subcarriers for performing a
contention-free random access procedure. Receiving module 1330 may
include a receiver and/or a transceiver. Receiving module 1330 may
include a receiver and/or a transceiver, such as transceiver 1010
described above in relation to FIG. 10. Receiving module 1330 may
include circuitry configured to wirelessly receive messages and/or
signals. In particular embodiments, receiving module 1330 may
communicate received messages and/or signals to determining module
1310. The functions of receiving module 1330 described above may,
in certain embodiments, be performed in one or more distinct
modules.
[0108] Input module 1340 may receive user input intended for UE
110. For example, the input module may receive key presses, button
presses, touches, swipes, audio signals, video signals, and/or any
other appropriate signals. The input module may include one or more
keys, buttons, levers, switches, touchscreens, microphones, and/or
cameras. The input module may communicate received signals to
determining module 1310. The functions of input module 1340
described above may, in certain embodiments, be performed in one or
more distinct modules.
[0109] Display module 1350 may present signals on a display of UE
110. Display module 1350 may include the display and/or any
appropriate circuitry and hardware configured to present signals on
the display. Display module 1350 may receive signals to present on
the display from determining module 1310. The functions of display
module 1350 described above may, in certain embodiments, be
performed in one or more distinct modules.
[0110] Determining module 1310, communication module 1320,
receiving module 1330, input module 1340, and display module 1350
may include any suitable configuration of hardware and/or software.
UE 110 may include additional modules beyond those shown in FIG. 13
that may be responsible for providing any suitable functionality,
including any of the functionality described above and/or any
additional functionality (including any functionality necessary to
support the various solutions described herein).
[0111] FIG. 14 is a schematic block diagram of an exemplary network
node 115, in accordance with certain embodiments. Network node 115
may include one or more modules. For example, network node 115 may
include determining module 1410, communication module 1420,
receiving module 1430, and any other suitable modules. In some
embodiments, one or more of determining module 1410, communication
module 1420, receiving module 1430, or any other suitable module
may be implemented using one or more processors, such as processing
circuitry 1120 described above in relation to FIG. 11. In certain
embodiments, the functions of two or more of the various modules
may be combined into a single module. Network node 115 may perform
the methods for providing contention-free random access resources
for NB-IoT described above in relation to FIGS. 1-9.
[0112] Determining module 1410 may perform the processing functions
of network node 115. As an example, determining module 1410 may
reserve, within a NPRACH resource comprising a plurality of start
subcarriers, a subset of the plurality of start subcarriers for
performing a contention-free random access procedure. Determining
module 1410 may include or be included in one or more processors,
such as processing circuitry 1120 described above in relation to
FIG. 11. Determining module 1410 may include analog and/or digital
circuitry configured to perform any of the functions of determining
module 1410 and/or processing circuitry 1120 described above. The
functions of determining module 1410 may, in certain embodiments,
be performed in one or more distinct modules.
[0113] Communication module 1420 may perform the transmission
functions of network node 115. As one example, communication module
1420 may communicate, to one or more UEs, information indicating
which of the plurality of start subcarriers within the NPRACH
resource are reserved for performing the contention-free random
access procedure. As another example, communication module 1420 may
communicate, to a first UE, an instruction to use a particular one
of the reserved start subcarriers for performing the
contention-free random access procedure. Communication module 1420
may transmit messages to one or more of wireless devices 110.
Communication module 1420 may include a transmitter and/or a
transceiver, such as transceiver 1110 described above in relation
to FIG. 11. Communication module 1420 may include circuitry
configured to wirelessly transmit messages and/or signals. In
particular embodiments, communication module 1420 may receive
messages and/or signals for transmission from determining module
1410 or any other module. The functions of communication module
1420 may, in certain embodiments, be performed in one or more
distinct modules.
[0114] Receiving module 1430 may perform the receiving functions of
network node 115. Receiving module 1430 may receive any suitable
information from a wireless device. Receiving module 1430 may
include a receiver and/or a transceiver, such as transceiver 1110
described above in relation to FIG. 11. Receiving module 1430 may
include circuitry configured to wirelessly receive messages and/or
signals. In particular embodiments, receiving module 1430 may
communicate received messages and/or signals to determining module
1410 or any other suitable module. The functions of receiving
module 1430 may, in certain embodiments, be performed in one or
more distinct modules.
[0115] Determining module 1410, communication module 1420, and
receiving module 1430 may include any suitable configuration of
hardware and/or software. Network node 115 may include additional
modules beyond those shown in FIG. 14 that may be responsible for
providing any suitable functionality, including any of the
functionality described above and/or any additional functionality
(including any functionality necessary to support the various
solutions described herein).
[0116] Modifications, additions, or omissions may be made to the
systems and apparatuses described herein without departing from the
scope of the disclosure. The components of the systems and
apparatuses may be integrated or separated. Moreover, the
operations of the systems and apparatuses may be performed by more,
fewer, or other components. Additionally, operations of the systems
and apparatuses may be performed using any suitable logic
comprising software, hardware, and/or other logic. As used in this
document, "each" refers to each member of a set or each member of a
subset of a set.
[0117] Modifications, additions, or omissions may be made to the
methods described herein without departing from the scope of the
disclosure. The methods may include more, fewer, or other steps.
Additionally, steps may be performed in any suitable order.
[0118] Although this disclosure has been described in terms of
certain embodiments, alterations and permutations of the
embodiments will be apparent to those skilled in the art.
Accordingly, the above description of the embodiments does not
constrain this disclosure. Other changes, substitutions, and
alterations are possible without departing from the spirit and
scope of this disclosure, as defined by the following claims.
[0119] Abbreviations used in the preceding description include:
[0120] 3GPP Third Generation Partnership Project
[0121] AP Access Point
[0122] BS Base Station
[0123] BSC Base Station Controller
[0124] BTS Base Transceiver Station
[0125] CDM Code Division Multiplexing
[0126] CPE Customer Premises Equipment
[0127] D2D Device-to-device
[0128] DAS Distributed Antenna System
[0129] DL Downlink
[0130] eNB eNode B
[0131] FDD Frequency Division Duplex
[0132] LAN Local Area Network
[0133] LEE Laptop Embedded Equipment
[0134] LME Laptop Mounted Equipment
[0135] LTE Long Term Evolution
[0136] M2M Machine-to-Machine
[0137] MAN Metropolitan Area Network
[0138] MCE Multi-cell/multicast Coordination Entity
[0139] MCS Modulation level and coding scheme
[0140] MSR Multi-standard Radio
[0141] NAS Non-Access Stratum
[0142] NB-IoT Narrow Band Internet-of-Things
[0143] NPDCCH Narrowband Physical Downlink Control Channel
[0144] NPRACH Narrowband Physical Random Access Channel
[0145] OFDM Orthogonal Frequency Division Multiplexing
[0146] PDCCH Physical Downlink Control Channel
[0147] PDSCH Physical Downlink Shared Channel
[0148] PRB Physical Resource Block
[0149] PSTN Public Switched Telephone Network
[0150] PUSCH Physical Uplink Shared Channel
[0151] PUCCH Physical Uplink Control Channel
[0152] PRACH Physical Random Access Channel
[0153] RA-RNTI Random Access-Radio Network Temporary Identifier
[0154] RB Resource Block
[0155] RNC Radio Network Controller
[0156] RRC Radio Resource Control
[0157] RRH Remote Radio Head
[0158] RRU Remote Radio Unit
[0159] TDD Time Division Duplex
[0160] TS Technical Specification
[0161] UE User Equipment
[0162] UL Uplink
[0163] WAN Wide Area Network
* * * * *